Method of assembling electrical measuring instruments



J. L. AXEN.

METHOD OF ASSEMBLING ELECTRICAL MEASURING INSTRUMENTS.

APPLICATION FILED APR. 19, 1920.

1,419,999., P tentedJune 6, 1922.

JOHN L. AXEN, or OAK PARK, ILLINOIS, ASSIGNOR T0 NATIONAL GAUGE & EQUIP-MENT COMPANY, or LA onossn, WISCONSIN, A CORPORATION or WISCONSIN,

METHOD OF ASSEMBLING ELECTRICAL MEASURING INSTRUMENTS.

iaoco.

Specification of Letters Patent.

Patented June 6, 1922.

Original application filed June 12, 1919, Serial No. 303,783. Dividedand this application filed April 19, 1920. Serial No. 374,823.

To a whom it may concern:

Be it known that 1, JOHN L. AxnN, a citizen of the United States,residing at Oak Park, in the county of Cook and State of Illinois, haveinvented certain new and useful Improvements in Methods of AssemblingElectrical Measuring Instruments, of which the following is aspecification.

My invention relates to the method of assembling the parts of anelectrical measu ring instrument, it particularly relating to the methodof inserting and adjusting a bearing for the spindle of such instrumentin a manner to permit the parts to be more readily assembled andadjusted; this application being a division of my application Ser. No.303,783, filed June 12th, 1919, now Patent No, 1,342,840, dated June8th, 1920.

The object of my invention is to provide a more simple and effectivemethod of inserting and ad usting a bearing for the indicating needlestaff of a measuring instrument, which also facilitate the assembling ofthe parts in a complete device.

In the accompanying drawings Fig. 1 is a sectional view of an instrumentembodying my improved method, the section being'on the line 1-1 of Fig.2.

Fig. 2 is a front elevation with the dial, its glass cover and retainingcap for the same removed. v

Fig. 3 is an enlarged view of a portion of the base, member of thecasing as shown in Fig. 1, together with a portion of the pointer staffand lower bearing for the same.

Fig. 4 is a view similar to Fig. 3 with the pointer shaft and itsbearing removed.

Fig. 5 is an enlarged section of the hearing for the lower end of theindicator sta ff.

Fig. 6 is a view of the apparatus employed in carrying out my improvedmethod. the view being a sect-ion on the line (3-6 of Fig. 7theoperating parts on the instrument base being omitted.

Fig. 7 is also a view of the same apparatus. the same being a side view.

Fig. 8 is an end view ofthe apparatus.

Referring to the drawings. the instrument to which my improvedmethodjhas been applied is constructed as follows: casing is providedconsisting of a cylindrical side wall 10, a base portion 13. preferablyof soft metal having a flange 14. the casing being secured to the flangeby screws 15. The upper edge of the casing has a flange 11, the openingin the casing being closed by a glass 12. An indicating pointer shaft 16has its upper ends journaled in a bear ng 17, carried at the end of afinger 18, integrally formed with and projecting centrally from a bar18, which bar is secured by screws '19 to posts 20 which are integrallyformed with the base 13. The staff has secured thereto as at 25 a needleor pointer 2-1 which projects through the arcuate opening of the dial21, which dial is secured by the screws 22 to wings on the respectiveends of the cross bar 18. .The lower end of the pointer shaft is carriedby a bearing to be hereinafter described, the peculiar method ofinsertion of the same forming one of the features of my invention. Thestafi has attached thereto fan blades 33, each of which is located in afan-shaped chamber 30 closed at the top by a removable cover 31 securedin position by the screws 32, the stafi extending between the adjoiningapexes of the chambers.

Connected to the staff is. an elongated armature 34 of magneticmaterial, WhlCh is influenced by a current carrying coil consisting of afiat strip of metal indicated in a general way by the numeral 35. Thecoil terminals being secured to the posts 36 and 37. The flat strip ofmetal comprising the coil extends about the armature, the coilconsisting of three layers which are formed with aligned perforations asindicated at 35 to permit the passage therethrough of the staff 16, theperforation in the upper layer of the coil being elongated to alsopermit the passage therethrough of the elongated armature 34.

A permanent magnet 47 is bent on an arch to conform to the curvature ofthe periphery of the base and is secured at its opposite end by screws48 upon posts 49 preferably formed integral with the bottom wall of thebase, the magnet being'mounted at the side of the base opposite to thearmature 3i and cOil 35. From the poles of the magnet there areextendedtherein strips 47 of cast iron or similar permeable material oflow magnetic retentivencss, their-ends being connected directly to themagnet 4:7 by means of the magnet mounting screws 48.

These strips extend from the poles of the magnet upwardly and away fromthe poles in a plane a short distance above the upper core 35 of thecoil; the extreme ends of the strips being bent inwardly toward thestaff so as to lie above the armature 34 at opposite sides of the staffAs before stated, one of the features of my invention is the method ofinserting the lower bearing for the staff 16; this hearing is in thenature of a cylindrical disk 50, one end being cupped out as at 51 toform a seat for the pointed ends of the staff. The base is punched fromthe inside with an opening 52 to receive the bearing, the opening beingof a size so that the hearing will have a tight fit therein, the bearingbeing also inserted from the inside of the base. There is shown in Figs.6, 7 and 8 one form of apparatus which may be employed in carrying outmy method. After the operating parts have been assembled upon the base,the base is placed in an opening 60 of a block 60, the walls of theopening being provided with a shoulder 63 against which the base rests.The block is mounted upon a supporting base portion 61 and has at oneside thereof a projecting boss 62 and at the opposite side thereof aprojection 68 which has an open ended slot 68*. Hinged to the boss 62 bythe pivot screw 65 is a bar 64, a washer 66 being preferably insertedbetween the head of the screw and the bar. The bar is provided with athreaded opening 64* to receive the threaded portion 57 of a tool 58,having at its extreme end a reduced portion 59. When the bar 64 is swungto the position shown in the drawings with its free end resting in theslotted portion of the projection 68, the reduced portion 59 of theatoolwill be brought in line with the bearing 50 so that by turning the toolin the threaded opening of the bar the reduced portion 59 will bearagainst the bearing 50, and the bearing can be adjusted to the properderee. The walls of the opening 60 beyond the shoulder are formed withtwo recesses 70 to accommodate the posts 20, which also prevents thebase 13 from turning. After this operation the burrs about the edge ofthe opening which have resulted from the punching operation are pressedin against the bearing, as indicated in Fig. 3, by any suitable tool.This method furnishes a means for imparting a very fine adjustment tothe bearing, the fit of the bearing in the opening in the base beingsufficiently tight to hold the bearing in its adjusted position.

In assembling the parts, the fan blades 33 are placed within thechambers, the coils secured in position by fastening the terminalsthereof to the posts 36 and 37, the staff with the armature 34 andpointer 20 secured thereto, then being inserted through the alignedapertures of the coil with the lower ends of the staff projected throughthe curled ends of the fan blades with a tight fit so as to frictionallybind the fans to the staff, and the bar carrying the bearing 17 is thensecured in position with the respective ends of the staff located inthat bearing and also the base bearing, after which the base bearing isadjusted in the manner before described.

Having thus described my invention, I claim l. The method of providingbearings for a spindle, or the like, consisting in inserting a bearingin a plain cylindrical opening in a bearing carrying support, placingthe spindle in position with one end thereof coincident with saidinserted bearing, placing in position a bearing at the other end of saidspindle, and finally adjusting the spindle in said bearings by pressingsaid inserted bearing to its proper position against the adjacent end ofsaid spindle by the thrusting action of a tool.

2. The method of adjusting and securing 'a bearing in an opening formedin a bearing support by a punching operation which I consists ininserting a plain cylindrical bearing in said opening, adjusting saidbearing by forcing the bearing to its adjusted position by a pressingaction, and pressing the burs of metal caused by the punching operationinto said opening against said bearing.

3. The method of adjusting and securing a bearing consisting inproviding a metal support with a punched opening, inserting a plaincylindrical bearing member in said opening, adjusting said bearingmember by the thrusting action of a tool by causing the end of said toolto abut the bearing so as to force the same to its adjusted position,and afterwards pressing the burrs of metal caused by the pushing actioninto said opening against said bearing.

4. The method of providing bearings for a staff, spindle or the like,consisting in providing a fixed bearing for one end thereof, providing ametal support with an opening at the other end thereof, inserting aplain cylindrical bearing member into said opening with a tight fit, andadjusting said bearing member to the adjacent end of said staff by thethrusting action of a tool by. causing the ends of said tool to abut thehearing so as to press the same in said opening against the adjacent endof said staff for the purpose of positioning said staff properly withrespect to both of said bearings.

In testimony whereof, I have hereunto set my hand this 12th day ofApril. 1920.

JOHN L. AXEN. Witnesses:

BYRON C. THORPE, AUGUST F. SOBOTKA. Sr.

